METHOD FOR PREPARING PHENYLALANINE DERIVATIVES HAVING QUINAZOLINE-DIONE SKELETON AND INTERMEDIATES FOR USE IN THE PREPARATION OF DERIVATIVES
申请人:KATAOKA Noriyasu
公开号:US20090318688A1
公开(公告)日:2009-12-24
A method for preparing a phenylalanine derivative having a quinazoline-dione ring represented by the following formula (1) or a pharmaceutically acceptable salt thereof, comprising the following steps (a), (b) and (c):
(a) reacting an acyl phenylalanine derivative represented by the following formula (2):
with a carbonyl group-introducing reagent and a specific anthranilic acid derivative to thus form the corresponding carboxy-asymmetric urea derivative;
(b) converting the carboxy-asymmetric urea derivative into the corresponding quinazoline-dione derivative in the presence of a carboxyl group-activating agent:
(c) if desired, substituting an N-alkyl group for the hydrogen atom bonded to the nitrogen atom present in the quinazoline-dione ring of the quinazoline-dione derivative using an N-alkylation agent and then deprotecting the resulting product, when the substituent R3′ which is a group corresponding to R3 is protected. According to this method, there can be obtained a phenylalanine derivative having a quinazoline-dione skeleton in a industrially favorably high yield.
METHOD FOR PREPARING PHENYLALANINE DERIVATIVES HAVING QUINAZOLINE-DIONE SKELETON AND INTERMEDIATES FOR USE IN THE PREPARATION OF THE DERIVATIVES
申请人:KATAOKA Noriyasu
公开号:US20110313154A1
公开(公告)日:2011-12-22
A method for preparing a phenylalanine derivative having a quinazoline-dione ring represented by the following formula (1) or a pharmaceutically acceptable salt thereof, comprising the following steps (a), (b) and (c):
(a) reacting an acyl phenylalanine derivative represented by the following formula (2):
with a carbonyl group-introducing reagent and a specific anthranilic acid derivative to thus form the corresponding carboxy-asymmetric urea derivative;
(b) converting the carboxy-asymmetric urea derivative into the corresponding quinazoline-dione derivative in the presence of a carboxyl group-activating agent:
(c) if desired, substituting an N-alkyl group for the hydrogen atom bonded to the nitrogen atom present in the quinazoline-dione ring of the quinazoline-dione derivative using an N-alkylation agent and then deprotecting the resulting product, when the substituent R3′ which is a group corresponding to R3 is protected. According to this method, there can be obtained a phenylalanine derivative having a quinazoline-dione skeleton in a industrially favorably high yield.